This invention relates to automotive muffler forming machinery, and more particularly to a machine for deforming tubular muffler components into a mechanically joined muffler subassembly. The invention also relates to a process of forming a mechanically joined muffler subassembly, and the assembly as formed by the inventive process.
Focusing on the formation of automotive mufflers, mechanical lock joints have been invented which mechanically join muffler components in superior fashion. U.S. Pat. No. 4,565,260 issued on Jan. 21, 1986 to Wayne Scheidt et al. discloses such an invented joint. A mechanical lock joint is superior in its ease of inspection, maintenance of internal structure of the component materials, maintenance of continuity of protective coatings, ease of handling, lack of material distortion and the like. Nevertheless, serious problems have attended the formation of such lock joints in the accuracy of the joint forming machinery, the energy required, the longevity of the machine, and the ease and speed of maintenance, among others.